Car-brake



(No Model.)

b e e h s m e e. h S.. 4 m. DE YM w3 .R Am

No. 872,890. Patented Nov. 8, 1887.

INVENTOR z WITNESSES:

,lfm l 8 ATTORNEY.

N. PETERS. Phnwmnngmpmr. wnsmncm u. c.

(No Mod-el.) 4 Sheetsf-,Sheet 2.

G. A. BOYDEN.

UAR BRAKE.

N0. s7z,890, PatentedN0v.8',1s87.

VVITNESSESIv INVENTORI ATTORNEY.

N. PETERa Phmulhugmphcr. washington. D. C.

(No Model.)

GAR BRAKE.

Patented 1*Tov.'8,`188'7.,I y

ATTORNEY,

(No Model.)

G. A. BOYDEN.

GAR BRAKE.

No. 372,890. Patented Nov. 8, 1887.

IHIIII I I Illllll IIHII WITNESSES I INVENTOR I 20. fc3 l BY @QA ATTORNEY.

NA PETERS Phnln-Llllmgmpber. Washillgon. D. C4

UNITED STATES GEORGE A. BOYDEN, OF BALTIMORE, MARYLAND, ASSIGNOR TO THE BOY- DEN POWER BRAKE COMPANY OF BALTIMORE CITY, OE MARYLAND.

CAR-BRAKE.n

SPBCZIFICATION forming partof Letters Patent No. 372,890, dated November 8, 1887.

Application filed August 26, 1887. Serial No. 247,916. (No model.) v

To all whom it may concern:

Be it known that I, GEORGE A. BOYDEN, a citizen of the United States, residing at Baltimore, in the State of Maryland, have in- Vented certain new and useful Improvements in Oar-Brakes, of which the following is a specification. r

My invention relates to brakes for railroadcars wherein the brakes are applied by the pressure of springs and released, controlled, and held off by the pressure of compressed Afluid supplied through a continuous train-pipe leading from the locomotive.

It is essential to a practical car-brake that the brake-shoes when not against the wheels for braking shall be so far removed from the wheels as to entirely avoid contact therewith. To provide for this movement of the brake shoes .and also to allow for the leverage in the foundation gear77 of the brake mechanism now generally used on cars, requires that the prime mechanical power (which in the well- -known airbrake is a cylinder-piston and in the brake herein described is a spring) shall u have a movement or stroke of about seven to ten inches and a pressure of about four thousand pounds. To obtain this movement and pressure direct from one or more springs would require them to have Vdimensions so large as tov be unwieldy and impracticable for a car-brake. The first object, therefore, of my invention is to provide means in combination with a spring whereby the pressure resulting from the tlrst portion of the springs movement will be indirectly applied and said movement so increased by the coaction of other mechanism'as to take up all the slack in the foundation gear and place Vthe shoes in contact with the car-wheels, and then the pressure resulting from the latter portion of the springs movement will be directly applied with its full power to force said shoes hard against the wheels.

Where a spring is the prime mechanical power for applying and compressed fluid the medium for releasing the car-brakes, it is a desideratum that when the brakes are not in use with the compressed fluid the spring shall be kept in a state of as great relaxation as possible, in order thereby to preserve its elasticity and power. The second object, therefore,of my invention is to provide such a convcar, a difficulty in doing the most effective braking without sliding the car-wheels arises from the fact that some of the cars in the same train may be loaded heavily, some lightly, and some may be without load. It is important, therefore, in order to do the most effective braking tov be able to apply the shoes to the wheels of each car with as great pressure as 7o the load on the car will permit; but the' pressure should always be somewhat less than the weight that is on the axles. The third obj ect, therefore, of my inventionvis to provide means whereby the pressure to be exerted by the spring on the foundation gear of each car of a train may be conveniently changed and regulated by the ordinary hand-Wheel, so as to be greater or less and to correspondiwith the load each car may be carrying.

The invention is illustrated in the accompanying drawings, (four sheets) in which- Figure 1 is a View, partly in section, of the prime power or combined spring device, showing the position when the brakes are oft. Fig. 2 is a view of the same, showing the position of the parts after the rst portion of the springs movement. Fig. 3 is a view of the same, showing. the position of the parts when the brakes are on, that is, after the lat- 9c ter portion of the springs movement. Fig. 4

is a sectional view showing a modification in the construction of the prime power or combined spring device, showing the position when the brakes are 0H. Fig. 5 is a view of 95 the same, showing the position of the parts when the brakes are on-that is, after the latter portion of the springs movement. Fig.

6 is a transverse side view, partly in section,

of the modication seen in Fig, 5, and showrooing the two spring-pockets. Fig. 7 is a top plan view of a car-frame,showing that part of the foundation gear which connects the prime mechanical power or spring, as illustrated in Fig. l, and the ordinary hand-wheel. Fig. 8 is a longitudinal section of a car, showing the foundation gear, with theordinary hand-wheel and prime mechanical power or combined spring device. Figs. 9 and 10 show side and cross-section views of the combined spring device, illustratinga modiiication in the position ofthe slack-lever,and showing foursprings and pockets. Figs. 1l and 12 show side and crosssection views of the combined spring device, illustrating the same modication in the posi tion of the slack-lever, and showing one sprin g and pocket.

The car is designed to be equipped with u any ordinary or well-known foundation'gear brake mechanism, which includes shoes x, brake-beams y, and levers c on the trucks, and the rod or chains and levers which connect these parts with the prime-power spring and ordinary hand-wheel, and said foundation gear is arranged to be operated as usual,when ever it may be desired, by the well-known hand-wheel b ou an upright shaft.

The first part of my invention relates to the combined spring device which constitutes the prime mechanical power for applying the brakes.

The letter A designates an expansible chamber Afor compressed tluid. This chamber in the present instance is a metal box or drum having a rigid side, o, and a movable side, d. The form of movable side here shown is that commonly called a iexible diaphragm,7 which is secured to the metal box part in any suitable manner. Other known forms of expansible chamber-such as a cylinder and pis ton--may be used. The iiexible diaphragm d is re-enforced on both sides by plates d.

An opening, e, in the rigid side of the chamber or box provides for a connection with the train-pipe B, and a frame or open cover, f, is secured to the said metal box c over the ilexible diaphragm. One or more tubular-shaped pockets, C, are rigidly secured, each by one end, to the said frame or coverf, and project therefrom, and, longitudinally considered, these pockets have position at a right angle with respect to the said movable side. A spiral spring, D, occupies each pocket, and one end ofeach spring is in contact with one of the diaphragm-plates d, and normally presses the iiexible diaphragm d toward the rigid side c of the chamber. It will be seen that when iluid under pressure enters the expansible chamber A at the train-pipe connection e the flexible diaphragm is expanded, as shown in Fig. l, and the springs D will be contracted and put in the condition of greatest tension and the brakes held ed. When the reverse action of the flexible diaphragm takes placethat is, when fluid-pressure is exhausted from the chamber A-the springs will expand,cans ing the flexible diaphragm to collapse or take position against the rigid side c of the chamber, and then the springs will be in the condition of greatest relaxation, and thereby, in

the normal operation of the device, the brakes will be applied.

The expansible chamber A may be located and secured on the car-frame E at any desired point. The trainpipe Bis arranged in a wellknown way, so that its terminals will be at diagonally-opposite corners of the car-ends, whereat the hose-couplingsg areattached. The branch pipe 71, from the train-pipe B to the expansible chamber A has a cock, 71.', whereby the said chamber and the spring on the ear may be cut out from the action of the compressed fluid supplied through the train-pipe.

Reference will now be made to the mechanism connecting the foundation-gear and spring. A slack lever, F, (see Figs. 1, 2, 7, and 9,) has a slot,.i, the greatest dimension of which is in the direction of the length of the lever, and the lever is pivoted through the said slot by aixed pin, 7c. Where two springpockets are used, as in Figs. l, 2, and 3, the pivot-pin may be secured between the two springpockets (l. The slot has at one end a side notch or slight offset, l, which, while the lever is turning serves as a bearing to rest on the said pivot-pin k. The slack-lever F may therefore turn on the fixed pivot-pin k, and when it has turned from the position shown in Fig. 1 as far as it is permitted to the position shown in Fig. 2, it will disengage from the pivot k and slide in the direction of its length toward the flexible diaphragm.

The slack-lever F, having the slot t' and the fixed pivotpin k, comprises disengaging mechanism77 which in this combination is productive of important results, hereinafter explained. The diaphragm-rod G has one end connected with the movable side d of the expansible chamber and the other end jointed atm to the slack-lever F. When the movable side of the expansible chamber, through the diaphragm-rod G, draws on the slack-lever F, the latter will first turn through an arc of about ninety degrees from the crosswise position which it has in Fig. l to an endwise position, as in Fig. 2. This turning of the slacklever is effected by the first portion of t-he springs movement, and the end of the powerrod n is placed in theoifsetzof the diaphragmrod G, and the jointing-pin j slightly beyond the center line of the said diaphragm-rod,and thereby the slack-lcver F will be retained in the latter position, and while so retained the power-rod n and the diaphragm-rod G will in effect act as one rod, whereby the full pressnre of the latter portion of' the springs movement will be applied directly to the foundation gear to force the brake shoes hard against the wheels. A system of rods (or chains) and levers, (see Figs. 7 and 8,) which will be presently described,connects the slacklever F with the levers of the foundation gear, which latter levers are located at a. It will now be seen that when duid-pressure is ex hausted from the expansible chamber the contracted springs D will begin to expand or IOO IIO

move out, and an important result follows-V to wit, the first ,portion of the springs movement (in practice a movement of about an inch) will turn the slack-lever F on its pivot,

Vand the greatly-increased movement of the free end of this lever will be sufficient to take up all the slack in the brake mechanism and place the brake-shoes in contact with carwheels. Thus the first portion of the spring-s movement is indirectly applied to take up the slack, and then when the slack-lever F has turned to an endwise position with respect to the said movable side d of the chamber it so disengages from the pivot-pin k that said pin ceases to act as a pivot, and the latter portion of the springs movementin practice a movement of about two or three inches-with its full pressure will be directly applied to force the brake-shoes hard against the wheels.

Thesystemof rods (or chains) and levers before referred to consist of a, power-rod, n, jointed by one end to the slack-lever F and by the other end to one end of a ioatiug lever, o, and a rod, p, connecting the other end of the said iioating lever o with the beam-lever a of the foundation gear on one truck. For the other truck is asimilar Boating lever, o, and rod p', and a rod or chain, r, connecting one end of the floating lever o with the upright shaft of the hand-wheel b. A central rod, q, connects the said two floating levers o and o. By this connection between the brake-spring D and the ordinary hand-wheel shaft the brakes 'may be operated by the combined action of the said spring and theconipressed fluid or by the' ordinary hand-wheel. Furthermore, I

Vobtain the desideratum that whenever the 'can brakes are operated alone with the ordinary hand-wheel the spring will be and will remain in the condition of its greatest relaxation, at which time ,the power. of a brakeman, as ordinarily exerted at the hand-wheel b, will not be sufficient to affect this condition of the spring. When the brakes are applied by the spring, the end w of that Iioating lever o which is connected with the handwheel shaft becomes a fixed point, and whenjthey are operated by the hand-wheel shaft the end y' o`f that floating lever o which is connected with the` powerrod n becomes a fixed point. Whichever way the brake may be applied-by the spring D or by the hand-wheel b-the pressure exerted will be equal or alike on-all the shoes .r of the In the combined spring device shown in Figs. 1, 2, and 3 two pockets C and two springs D are employed, and the disengaging slacklever F is pivoted between the two pockets.

My invention of this combination, however, is not limited to any particular number of pockets or springs, nor to a precise position ofthe slack-leverwith respect thereto. tion of this, Figs. 9 and 10 show four springpockets and four springs, and the slack-lever F is pivoted between two arms,fv o', attached at the end of the pockets, and which project therefrom. In Fig. 9, and also Fig. l1, one

In illustra-v The combined spring device,embracing the expansible chamber, the spring, and a disengaging slack take-up, is not limited to a particular form of slack take-up, such as the lever F shown in Figs. 1, 2, and 3. In illustration of this Figs. fi, 5, and 6 show a modification whereby the same result is produced. The modication has a compound lever, H, of the form known as lazy-tongs, and a pulley, I, is carried by the levers H. A plate or bracket, J, is xed to each of the two springpockets C, and the two short arms u, of the lazy-tongs lever H are each pivoted by a separate fixed pin, la', to said brackets, and the end of these two arms are provided with cogteeth l. The long arms are jointed to the short ones by a pin, t, and are jointed together by apinj, which also carries the pulley I. Two parallel plates, G', are attached to the diaphragm-plates d, and two cross-bars, s, each lhaving rack teeth z" on its outer side, connect the said two parallell plates. When the brakes are off, the parts have the position shown in Fig. 4. The cog-teeth Zof each short arm engages with the rack-teeth t" on one of the connecting bars s. The two plates G carry two pulleys, m', the position of which with respect to the pulley l, carried by the le-` vers, is such vas to form a V-shaped triangle. A chain, g', passes under the pulley I on the compoundslack-lever or lazy-tongs H.l Then one part of the chain passes over one of the said plate -pulleys m', and thence extends toward one truck of the car, whilethe other part of the chain passes over the other platepulley m', and extends toward the other truck.

Each end of this chain is attached to separate floating levers o and o. When thesprings in vthe pockets C expand, the movab'le side d of the expansible chamber is pressed toward the rigid side c, and carries the plates G', toothed bars s, and pulleys fm. Thereby the two short arms u of the lazy-tongs which are pivoted by the fixed pin 7c will, by the action of the geared teeth 1J Z', turn from the position which they have in Fig. 4, through an arc f about ninety degrees, to the position shown in Fig. 5, and thereby the long arms and pulley I will be moved, as shown, in a direction away from the expansible chamber A, and by drawing on the chain q will take up the slack in the br'ake mechanism. This result is attained by 4the first portion of the springsv movement.

IOO

then the latter portion of the springsmovement, with full pressure acting on the mova- -fluid from the trainpipe.

blc side of the chamber d, parallel plates G', two pulleys m', and chain q', will be directly applied to force the brake-shoes hard against the wheels.

In operating this brake on a train of cars the train-pipe B should iirst be connected with the locomotive and thence throughout the train. The brakes of all the cars must then be applied by the hand-wheel b on each car-the pressure exerted on the different cars being made to correspond, as near as may be possible, with the load each car maybe carryingaiid the liandwheel shalt secured from accidental releasing by a suitable pawl, b', after which the brakes are to be operated by the action of the spring and the compressed tluid, and controlled entirely by the engineer in the following manner: Asjust stated, the brakes before starting are first applied by the handwlieel on each car. Vhen it is desired to release the brakes, the engineer turns the usual brake-cock to permit compressed fluid to pass from the usual reservoir on the locomotive to the train-pipe B, which supplies all the expansible chambers A, and thereby compresses or contracts the springs D and releases the brakes. As long as the trainpipe is full of compressed air or other fluid, the brakes will be held ofi". Vhen the engineer desires to ap ply the brakes, wholly or partially, lie releases the compressed fluid or allows it to escape from the traiirpipe in accordance with the brake-pressure which is to be applied to the car-wheels. It will be seen that the brake is fully under the control of tlie engineer, and in case ofthe train accidentally separating in two or more parts (which often occurs) the brakes on all the cars will be automatically applied by reason of the escape of the comp ressed In case any of the hose connections between the cars should burst, or from any cause the compressed fluid should escape, the brakes will be promptly applied by the action of the spring D and the train stopped. Vhen the locomotive is dis connected froni the train,the brakes on the cars will remain applied, and may be released by the handwheels b in the usual manner.

The spring as a prime mechanical power, to be used, as herein described, for applyingcarbrakes, has advantages over compressed iiuid, one of which is that as a braking-power certain to act in an emergency the spring will invariably insure control of a train, whereas air or other compressed iiuid is subject to leakage, to the chance of an insufficient airepressure ou the locomotive, and other incidents inherent to its use. Again, the spring and compressed fiuid, as here used, enables the engineer to apply to the car-wheels any desired amount of brake-pressure less t-han the maximum and to maintain the saine for anyleiigth of time, and, without releasing the said brake-pressure, to increase or lessen the same, as desired. Thus this spring-brake is better adapted for the requirements of the service. It is not essential that the springs employed be of the spiral forni. lt is also obvious that the parts herein shown and described may be varied or changed in their forni and construction, as two plans to secure this end are illustrated. Any suoli modifications, therefore, are within the scope of my invention.

It obvious that the essential feature of the invention liesin aninterposed movement-multiplying device arranged to operate during the iirst part of the movement of the spring, when less force is required to take up the slack,and then to allow the spring to act directly on the brake-lever.

The term slack, as herein used, is meant to include all looseness of parts and play between the joints or connections of the different parts of the foundation gear, and also the space which intel-venes between the brakeshoes and the car-wheels when the brakes are off.

The method of operation herein described is not claimed, it being the subject-matter of an application filed by mein the United States Patent Office September 5, 1887, Serial No. 248,506.

Having described my invention, I claim and desire to secure by Letters Patent of [he United Statesl. A mechanism for actuating railway-cai' brakes, comprising the combination on each car of an expansible chamber for compressed fluid, a spring for applying the brakes, and a disengaging slack-take-u p device,whereby the iii-st portion of the springs movement is applied to the slack-take'up device and the latter portion of the springs movement is applied to force the brakes hard against the wheels.

2. In a car-brake, the combination of the foundation gear, an expansible chamber, a train-pipe having its terminals at opposite ends of the car and connected with said expansible chamber, a spring for applying the brakes, and a disengaging slack-take-up device connecting the movable side of the said chamber with the foundation gear.

3. A mechanism for actuating railway-car brakes, comprising the combination on each car of au expansible chamber, A, springpockets C, containing springs, a slack-take-up device attached to the said springpockets,and a connection uniting the said movable side of the chamber and slack-take-up device.

4. A mechanism for actuating railway-car brakes, comprising the combination of the box or drum c, a frame or cover, f, secured to the said box or drum, a flexible diaphragm, d, clamped between said box and frame, a spring, D, bearing on the diaphragm, and a disengaging slack-take-up device, for the purpose set forth.

5. A mechanism for actuating railway-car brakes, comprising the combination of the box or drum c, a frame or cover, f, secured to the said box or drum, a flexible diaphragm, d, clamped between said box and frame, a tubular pocket, C, secured to the said frame, a

IIO

IIS

spring, D, occupying the pocket, and a disengaging slack-take-up device, for the purpose set forth.

6. A mechanism for actuating :railway-car brakes, comprising the combination of an expansible chamberforcompressed Huid, aspring, a fixed pivot-pin, la, a lever pivoted by said pivot-pin, and also adapted to slide thereon, and a connection, G, uniting the movable side of the eXpansible chamber with the said lever, whereby the first portion of the springs movement is converted into a greater movement by the swing of the lever and the latter portion of the springs movement is applied direct by the sliding of the lever. v

7. In a car-brake, the combination of the foundation, gear, an expansible chamber, a

train-pipe having its terminals at Opposite ends of the car, a branch pipe, h, connecting the trainpipe with the expansible chamber, and having a cutoff-cock, h', a spring for applying the brakes, and a disengaging slack-take-up device connecting the movable side of the said chamber with the foundation gear.

8. In a car-brake, the combination of the hand-wheel, a spring for applying the brakes, an lexpansible chamber for compressed fluid, a disengaging slack-take-up device, and foundation gear connecting with both the said hand-wheel and spring.

9. A car-brake-actuating mechanism,`con sisting of a spring, and expansible chamber for compressed fluid, arranged to compress the spring, connections between the spring and the brake-lever, and an interposed movementmultiplying device arranged to operate through the first part only of the movement of the spring, whereby the slack is first taken up and the power afterward directly applied, substantially as described.

In testimony whereof I afx my signature in the presence of two witnesses.

GEORGE A. BOYDEN.

Witnesses:

B. F. BOYDEN, Y JOHN E. MORRIS. 

